Ink fountain and method



Nov. 26, 1929. H. c. cHRoEDER 1,736,943

INK FOUNTAIN AND METHOD Original Filed July '7, 1926 2 Sheets-Sheet l Nov. '26, 1929. H. c. SCHROEDER 1,736,943

INK FOUNTAIN AND METHOD Original Filed J tlly 7, 1926 2 Sheets-Sheet 2 v I g INVENTOR. N y I ATTO Patented Nov. 26, 3929 UNITED STATES PATENT OFFICE HANS C. SCI-IROEDER, OF LA GRANGE, ELLINOIS, ASSIGNOE TO GG$S PRINTING IPRE$S COMPANY, A CORPORATION 01* ILLINOIS INK FOUNTAIN AND METHOD Original application filed July 7, 1926, Serial No. 120,909. Divided -a11d,this application filed August -9,

1927. Serial My invention relates to printing presses and more particularly to the lnk fountaln employed in printing presses, and to a method for keeping the pigment of the ink unipended claims.

The invention consists in the novel parts, constructions, arrangements, combinations, improvements and method herein shown and described. 7

The accompanying drawings, referred to 1 herein and constitutingapart hereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings Fig. 1 is a vertical section along line l-l;

Fig. 2 is a detail plan of the bailie used in the present invention;

Fig. 3 is a diagrammatic vertical section showing the automatic circulationof the ink in the formation of Fig; 1;

Fig. 4 1s a plan view, partly broken away,

of the formation shown in Fig. l. v

To more readily distinguish my invention from other inventions, and to complywith Section 4888 of the Revised Statutes,1 shall briefly refer to the form of ink fountain which is now commonly employed in printing presses.

The usual typeof ink fountain for a printing press is provided with a rotatable fountain roller which rotates aportion of its surface in contact with the ink in the fountain at all times, so as to-accumulate ink to be transferred to the ductorroll. At the point where the rotating surface of the roller emerges from the fountain there is positioned a doctoriblade whichserves to scrape the surplus ink from the surfaceof the roller. As the fountain roller rotates, it sets-up a local convection current or eddy inthe ink adjacent to its surface. This convection current travels with thesurface of the roller to the point of junction of. the roller with the doctor blade. Since a relatively small amount of ink is allowed to pass to the edge of the doctor blade, the convection current is rebuffed or turned away from the surface of the roller and travels in a reverse direction on a course slightly divergent fromv the. surface of the roller fora certain .distance, when it completes its circuit by beingdrawn back to the rotating roller surface. Thuszthere is set up in the ink a local convection current which, how-ever, fails .to-eifect thev great mass of ink in the fountain removed from the roller and which, therefore, is left dead or unagitated. After the press has been running for a comparativelyshorttimewit. is

found in practice that. thepigment is withdrawn or used up from the local. current of ink described aboveand consequently the ink which is picked up by the fountain roller becomes thin and loses color. 'Under; the present practice, when this'condition arises, the

. doctor blade has to be somewhat furthersep- I arated from the fountain-roller in order-t0 obtain sufficient color from the thin ink which is being fed from the loealcurrents. Again, in the present practice,-when the pressis idle there is, of course, no local convection current, so that the pigment throughout the body of the ink tends to settle to the bottom of the fountain thus causing an uneven distribution and mixture of the pigment with the ink and making it necessary to stir up the ink by hand or other means in order to secure a proper mixture. Ordinarily, in running color it is necessary for the p'ressman tostir up the ink in the fountain by hand about every 15 minutes.

By my invention I eliminate all these objectionable' features and insure that the pigment in the ink will be'unifor-mly an-dautm matically distributed throughout the ink in th fountain. It will not be necessary to adjust the doctor blade to permit an additional quantity of thin ink to be taken up by the fountain roller, for by use of the invention, the coloring content and the consistency of the ink will always be uniform, insuring uniformity of color in the printed product. Further, any tendency that the pigment has to settle out by gravity will automatically be corrected by currents of ink set up in the fountain.

My present invention is directed to a novel method of causing the local convection currents set up in the vicinity of the fountain roller of the ink fountain of a printing press to diverge from their natural paths and flow through the mass of ink in the fountain which is removed from the fountain roller in such a way as to thoroughly agitate said ink and set up and maintain an even distribution of the pigment therein. 7

My present invention is also directed to means for directing the flow of the above mentioned convection currents throughout the mass of ink in the fountain so as to obtain and maintain the most desirable mixture of the pigment or coloring matter in the ink.

The invention is further directed to effecting and maintaining the desired color and consistency of ink in the fountain by a method which requires the introduction of no forces other than those employed in the actual operation of an ordinary ink fountain.

Other features and objects of the invention will be further set forth in connection with the appended detailed description of the pres ent preferred embodiment and it will be understood that the foregoing general description andthe following detailed description Referring now to the embodiment of the invention, illustrated by way of example in the accompanying drawings, 21 (Fig. l) is a standard form of ink fountain for a printing press equipped with the ordinary form of overshot fountain roller 22, co-operating with the ordinary form of ductor roll (not shown). This fountain 21 is provided with the usual doctor blade 23, supported in any suitable manner by the set screw 23 and provided with the adjusting member 23", all as in the usual practice.

Means for deflecting the convection currents set up by the rotation of the fountain roller 22, which rotates in the direction indicated by the arrow, are provided for carrying out the method of my invention. A baffle plate 36 is mounted in the fountain in a plane substantially parallel to the bottom of the fountain 30, so that its forward edge 39 lies adjacent to the surface of the fountain roller 22, arms 37 to which baflie plate is attached by rivets 38, 38 extend to the rear wall 31, of the fountain where they are provided with hooks, 40, and clamping screws 33 which serve to clamp the arms to the fountain. As shown in Figs. 1 and 3, the rear edge 39 of the baiile plate is substantially removed from the rear wall 31 of the fountain, so that a considerable space lies between the rear wall and said rear edge of the baffle plate. By reference to Fig. 2, it can be seen that the baffle plate 36 divides the fountain into substantially two compartments.

As previously described, if it were not for the presence of the baflle plate in the fountain, a local convection current generated by the drag of the rotating fountain roller 22 through the ink would travel in a circuitous path along the periphery of the roller from the point A (Fig. 2) where the surface of the roller first contacts with the ink in the fountain, to the point B, where the doctor blade 23 joins the surface of the fountain roller 22. At this point since very little ink can escape between the periphery of the fountain roller and the edge of the doctor blade 23, the surplus current of ink will be scraped off by the doctor blade and together with the current of ink following the periphery of the rotating fountain roller, would be deflected or turned back from the doctor blade and caused to travel back down into the body of the ink slightly removed from the roller surface to some point C, where it would mingle again with the current of ink following the periphery of the fountain roller. In this way a local current in the vicinity of the roller surface is set up and maintained, upon which are attendant all the undesirable features previously described.

However, by virtue of my invention, a very different proceeding takes place. As shown in Fig. 2, the convection current of ink is set up at A and follows the rotating surface of the roller to the point D where it encounters the edge 39 of the baffle plate. The baflie plate serves to divide the convection current and deflects the lower part of it out of its natural course and away from the surface of the roller. The remainder of the current flows on between the edge 39 of the baffle plate and j the surface of the rotating roller 22 up to the point B where the greater part of it is detlected back by the doctor blade and starts downward on its usual course somewhat re-' Masses inoved from the roller surface, as previously described. However, the baffle plate which lies in the path of this divergent, downwardly directed stream, prevents it from following its natural return course and causes it to travel above the baifle plate as incicated in Fig. 3, and thence to the rear wall 31 of the ink fountain where it is again deflected and its direction of flow reversed. After this deflection and reversal takes place the current proceeds parallel to the bottom of the fountain and beneath the baffle plate to a point near A where it mingles with the convection current set up by the rotating surface of the fountain roller. In the meantime, that portion of the original convection current which was deflected at D by the edge 39 of the baffle plate travels downward and merges with the above described current flowing along the bottom of the fountain.

By the above description, it can be seen that a complete coming-ling and movement of all the ink in the fountain will be effected by the presence of the baffle plate, with all the advantages of thorough mixing of the pigment and the maintaining of a uniform consistency and coloring of the ink fountain, together with the other advantages heretofore set forth.

It is to be understood that the statement of the theory of operation of applicants invention is that founded on applicants understanding at the present time, but should not be construed as restrictive of the actual manner of operation, which is in practice to secure the results stated.

The invention in its broader aspects is not limited to the specific mechanism shown and described but departures may be made therefrom within the scope of the appended claims without departing from the principles of the invention and without sacrificing its chief advantages.

What I claim is 1. T he method of mixing and maintaining a constant mixture of the ink in the ink fountain of a printing press which comprises rotating the fountain roller at a speed sufficient to create a convection current by reason of the contact of the ink with the fountain roller, diverting a substantial portion of said current out of its natural course at one point in said course into the mass of ink which is out of contact with the roller, and similarly diverting the remainder of said current at a subsequent point in said course.

2. The method of mixing and maintaining a constant mixture of the ink in the ink fountain of a printing press which comprises rotating the fountain roller at a speed sufficient to create a convection current by reason of the contact of the ink with the fountain roller diverting a substantial portion of said current out of its natural course at a point in said course near the roller into the mass of ink which is out of contact with the roller, and similarly diverting the remainder of said current at a point in said course removed from the roller.

3. The method of mixing and maintaining a constant mixture of the ink in the ink fountain of a printing press which comprises rotating the fountain roller at a speed suflicient to create a convection current by reason of the contact of the ink with the fountain roller and reversing the direction of a substantial portion of said current, while permitting the remainder thereof to continue on its natural course.

4. The method of mixing and maintaining a constant mixture of the ink in the ink fountain of a printing press which comprises rotating the fountain roller at a speed sufficient to create a convection current by reason of the contact of the ink with the fountain roller reversing the direction of a substantial portion of said current, while permitting the remainder thereof to continue on its natural course, and later diverting said remainder into the remote portions of the fountain.

5. An ink fountain for a printing press including in combination an overshot fountain rolier adapted to rotate therein, a flexible fountain blade and means to deflect out of its natural course a substantial portion of the convection current of ink set up by the drag of the roller through the ink.

6. An ink fountain for a printing press including in combination an overshot fountain roller adapted to rotate therein, a flexible fountain blade and means to deflect from its upward course a substantial portion of the convection current of ink set up by the drag of the roller through the ink.

7. An ink fountain for a printing press including in combination an overshot fountain roller adapted to rotate therein and means to reverse the direction of a substantial portion of the convection current of ink set up by the drag of the roller through the ink, while permitting the remainder of said current to follow its natural course.

8. An ink fountain for a printing press including in combination an overshot fountain roller adapted to rotate therein and a baflie plate mounted in the fountain substantially parallel to the bottom thereof.

9. An ink fountain for a printing press including in combination an overshot fountain roller adapted to rotate therein and nearis to divide into two main streams the convection current set up by the drag of the roller through the ink, one of said streams going below and the other above said means.

10. The combination in an ink fountain of a printing press of an overshot ink roller, a fountain blade and a baffle plate mounted in the fountain, parallel to the bottom thereof, for the purpose of effecting and main.-

mining a proper mixture of the ink, one edge of the heme plate bemg adjacent to the overshot lnk roller a11d rem0ved from the fauntzun blade.

In testunony whereof, I have signed my name to thls speclficatlon.

HANS C. SCHROEDER. 

